Newly manufactured electronic devices are tested to =measure actual performance against expected performance. The expected performance may be performance metrics defined by a manufacturer or in an industry standard. For example, an electronic device which purports to be compliant with the Peripheral Component Interconnect-Express (PCI-Express) specification must meet the performance metrics defined therein. For example, a compliance requirement defined in the PCI-Express specification states that a PCI-Express compliant device should be able to support data communication on a high-speed link in the case of a frequency difference or offset between incoming high-speed data from a remote PCI-Express device and outgoing high-speed data from the device.
Traditionally, testing the above-mentioned compliance requirement was performed using bench-type equipment consisting of high-speed signal generators and signal analyzers which are clocked by independent clock sources. Using the bench-type equipment is economically viable only when testing devices with a single high-speed port. However, for high volume production, an automatic test equipment (ATE) system containing many digital channel resources is used. Thus, there is a need for a more efficient frequency offset test.